Relativistic quantum dynamics of scalar bosons under a full vector Coulomb interaction

The relativistic quantum dynamics of scalar bosons in the background of a full vector coupling (minimal plus nonminimal vector couplings) is explored in the context of the Duffin-Kemmer-Petiau formalism. The Coulomb phase shift is determined for a general mixing of couplings and it is shown that the space component of the nonminimal coupling is a {\it sine qua non} condition for the exact closed-form scattering amplitude. It follows that the Rutherford cross section vanishes in the absence of the time component of the minimal coupling. Bound-state solutions obtained from the poles of the partial scattering amplitude show that the time component of the minimal coupling plays an essential role. The bound-state solutions depend on the nonminimal coupling and the spectrum consists of particles or antiparticles depending on the sign of the time component of the minimal coupling without chance for pair production even in the presence of strong couplings. It is also shown that an accidental degeneracy appears for a particular mixing of couplings.Comment: 8 pages, 1 table. arXiv admin note: text overlap with arXiv:1403.603

WALKINSENSE VALIDATION: PRELIMINARY TESTS OF MOBILITY PARAMETERS

The purpose of this study was to perform a preliminary validation of a new electronic instrument for human movement and performance assessment in sports. Measurements of distance, walking speed, step length and frequency were acquired, for a small sample of 15 subjects in a track of 10 m length, and compared to reference data. Results show good repeatability and data agreement across several trials at three different selfselected walking speeds

Study of Gaseous Emissions Derived from the Combustion of Diesel/Beef Tallow Biodiesel Blends

Air pollution is one of the main environmental problems of modern society. The road and transportation segment is a key source of polluting gases worldwide. In its research for transportation’s emission reduction alternatives, the Brazilian government instituted a wide-spread biodiesel, adding 7% (B7) of biodiesel to the diesel used in the country. Therefore, studies such as this must be carried out to guarantee the environmental sustainability of the new matrix of renewable energies, with the useof biofuels, as well as evaluate the gases emitted to for the environment by the combustion of the same ones. This work was detected CO, CO2 and NO gas emissions released into the atmosphere from the combustion of blends diesel/beef tallow biodiesel in a bench-scale engine. Using electrochemical sensors, the of these gases concentration were successfully registered for two modes of operation of the engine diesel, low rotation, 3500 rpm, and high rotation, 7000 rpm. The CO levels in this experiment in low rotation varied between values minimum and maximum range of 866.7 to 1333.3 ppm, and in high rotation, ranging of 666 and 1000 ppm respectively. For the CO2 concentration in low rotation varied between values minimum and maximum range of 2.1 to 2.4%, and high rotation, ranging of 2.2 to 2.5%, and for NO concentrations of the samples for the mode low rotation had a variation of 83 to 109.5 ppm, and for high rotation were 81.7 to 98.7 ppm respectively

The influence of gait cadence on the ground reaction forces and plantar pressures during load carriage of young adults

Biomechanical gait parameters ground reaction forces (GRFs) and plantar pressures during load carriage of young adults were compared at a low gait cadence and a high gait cadence. Differences between load carriage and normal walking during both gait cadences were also assessed. A force plate and an in-shoe plantar pressure system were used to assess 60 adults while they were walking either normally (unloaded condition) or wearing a backpack (loaded condition) at low (70 steps per minute) and high gait cadences (120 steps per minute). GRF and plantar pressure peaks were scaled to body weight (or body weight plus backpack weight). With medium to high effect sizes we found greater anterior-posterior and vertical GRFs and greater plantar pressure peaks in the rearfoot, forefoot and hallux when the participants walked carrying a backpack at high gait cadences compared to walking at low gait cadences. Differences between loaded and unloaded conditions in both gait cadences were also observed.info:eu-repo/semantics/acceptedVersio

Analysis of the backpack loading efects on the human gait

Gait is a simple activity of daily life and one of the main abilities of the human being. Often during leisure, labour and sports activities, loads are carried over (e.g. backpack) during gait. These circumstantial loads can generate instability and increase biomechanicalstress over the human tissues and systems, especially on the locomotor, balance and postural regulation systems. According to Wearing (2006), subjects that carry a transitory or intermittent load will be able to find relatively efficient solutions to compensate its effects.info:eu-repo/semantics/publishedVersio

A Amazônia Azul: recursos e preservação

The area encompassed by the Brazilian Exclusive Economic Zone (EEZ) and its extensions is estimated to cover a total area of 4.5 million square kilometers, which corresponds to more than half of continental Brazil. This sea area over which Brazil is entitled to have some sort of sovereignty has been named Blue Amazon. Despite the enormous potential of resources existing in this EEZ, such as living resources, mineral resources, energy resources, and non-extractive resources – some of which have already been exploited – the perception of Brazilians as regards their sea and its resources is still incipient. One of the consequences of the lack of maritime mentality is that the exploitation of resources in the Brazilian EEZ is not always carried out in a sustainable mannerA área ocupada pela Zona Econômica Exclusiva (ZEE) brasileira e suas extensões é estimada em 4,5 milhões de quilômetros quadrados, sendo mais do que a metade da área do Brasil continental. Essa área marinha sobre a qual o Brasil exerce alguma forma de soberania tem sido denominada “Amazônia Azul”. Apesar do enorme potencial de recursos existentes na ZEE, tais como recursos vivos, recursos minerais, recursos energéticos e recursos não extrativos, alguns já em exploração, a percepção dos brasileiros a respeito do seu mar e dos seus recursos ainda é incipiente. Uma das consequências da falta de mentalidade marítima é a exploração nem sempre sustentável dos recursos da ZEE brasileir

Microstructure and morphoquantitative study of pineal gland in santa ines sheep

O presente estudo avaliou os aspectos morfoquantitativos e qualitativos da glândula pineal em fêmeas de ovinos da raça Santa Inês em atividade reprodutiva e anestro fisiológico. Foram utilizados sete ovinos, fêmeas e adultas, coletados em frigoríficos da região de Brasília-DF. Estes não apresentavam sinais clínicos relacionados a afecções do sistema nervoso. Os encéfalos foram retirados e suas dimensões mensuradas. Posteriormente foram seccionados para expor a glândula pineal e mensurar suas dimensões. Os fragmentos do diencéfalo, contendo a glândula pineal, foram submersos em solução aquosa a 20% de formaldeído e posteriormente submetidos a técnicas histológicas convencionais. Para a avaliação morfoquantitativa desta glândula, foram empregadas as colorações Hematoxilia-Eosina, Azul de Toluidina e Tricrômio de Gomori. O encéfalo teve um comprimento médio de 67,25 ± 1,75 mm e a largura média de 58,97 ± 4,0 mm. Já a glândula pineal apresentou o comprimento médio de 6,98 ± 0,79 mm e a largura média de 6,40 ± 1,35 mm. Diante da análise microscópica, foi obtida uma média de 86,27 ± 30,44 pinealócitos por campo. Ao ser aplicado o teste de correlação de Pearson, o número de pinealócitos apresentou fraca correlação linear negativa (r = -0,11) em relação ao comprimento da glândula pineal e uma fraca correlação linear positiva (r = 0,39) em relação à largura da mesma. Portanto o número de pinealócitos apresenta uma maior correlação com a largura da glândula do que com o seu comprimento. Mastócitos estiveram presentes em apenas um animal (14,28%) e as concreções calcareas foram observadas em dois animais (28,57%). A glândula se mostrou envolta por uma cápsula de tecido conjuntivo com ausência de projeções para o parênquima. _________________________________________________________________________________ ABSTRACTThis study examined morphologic aspects of the pineal gland in Santa Ines sheep in anoestrus physiological and reproductive activity. Seven female adult sheep were collected at slaughterhouses in the region of Brasilia-DF, with no clinical signs related to diseases of the nervous system were used. The brains were removed and their dimensions were measured. The brains were sectioned to expose and measure the pineal gland. The fragments of the diencephalon containing the pineal gland were immersed in 20% formaldehyde solution. Subsequently, the fragments were submitted to conventional histological techniques. The Hematoxylin-eosin, Toluidine blue and Gomori trichrome staining were used for a morphoquantitative analysis. The brain had an average length of 67.25 ± 1.75 mm and average width of 58.97 ± 4.0 mm. The pineal gland had an average length of 6.98 ± 0.79 mm and average width of 6.40 ± 1.35 mm. The quantitative analysis showed an average 86.27 ± 30.44 of pinealocytes per field. According to the Pearson correlation test, the number of pinealocytes showed a weak negative linear correlation (r = -0.11) with the length of the pineal gland and a weak positive linear correlation (r = 0.39) with the width. Therefore, the number of pinealocytes has a stronger correlation with the width of the gland compared to the length. Mastocytes were present in only one animal (14.28%). Calcareous concretions were observed in two animals (28.57%). The connective tissue formed the capsule surrounding the gland with no projections into the parenchyma

Force irradiation effects during upper limb diagonal exercises on contralateral muscle activation

The aim of this study was to explore the force irradiation effects of upper limb isometric diagonal exercises on shoulder muscle activities. Interactions among diagonal directions, contraction intensities (moderate and maximum) and sex were assessed. Thirty healthy subjects (11 males) performed isometric unilateral diagonal exercises based on proprioceptive neuromuscular facilitation technique in an isokinetic dynamometer with their dominant upper limbs. The second diagonal for flexion and for extension were assessed while the participants performed their maximum isometric torque (MIT) and at 25% of their MIT. During the exercise the muscle activity of the medial deltoid, pectoralis major and upper trapezius in the non-dominant (non-exercised) upper limbs of the participants was recorded by surface electromyography. The highest muscle activity occurred in the upper trapezius during the diagonal for flexion (27% of maximum isometric voluntary contractions). Upper trapezius and pectoralis major were more active during the diagonal for flexion than diagonal for extension (p 0.05). In conclusion, we observed that force irradiation during upper limb diagonal exercises is affected by diagonal direction, contraction intensity and sex when performed by healthy participants.info:eu-repo/semantics/publishedVersio